"The railway network will accelerate the mass movement of Chinese migrants into Tibet which will threaten the unique cultural identity of the Tibetan people through forced assimilation," a post on the CTA's official website said.
Chinese daily Global Times on Thursday said a railway line linking Lhasa and Shigatse in Tibet Autonomous Region, known as the "closest stretch of railway to the sky", is to open to traffic in August after finishing its 14th track test July 22.
It said the launch of the rail line that extends 254 km from Lhasa westwards to Shigatse will be the first in the southwestern area of Tibet.
Construction on the Lhasa-Shigatse line began in September 2010.
The mass influx of Chinese migrants into Tibet has also led to illegal land grabs by unscrupulous Chinese businessmen and authorities, said the CTA, headquartered in this northern Indian hill town.
Tibetans inside Tibet have protested against illegal land grabbing of their lands and rampant exploitation of mineral resources.
It said with the influx of the mining companies and rampant exploitation of Tibet's resources, the ecological balance of the fragile Tibetan plateau is exposed to severe risks of disasters.
The Chinese daily said the Lhasa-Shigatse rail line is an extension of the Qinghai-Tibet railway that runs from Xining, Qinghai Province to Lhasa. It will include 13 stations with altitudes ranging from 3,600 to 4,000 metres.
It is the largest infrastructure project during the 12th Five-Year Plan (2011-2015) with an investment of more than 10.8 billion yuan ($1.7 billion), said the paper quoting Yang Yulin, deputy director of the railway office of the Tibet government.
"It will accelerate transportation of mineral products, which can only be moved through highways that often risk being cut off during rainy season or see vehicles turning turtle," Zhu Bin, a manager with a mineral company based in Lhasa, told People's Daily.
Yang revealed that during the 13th Five-Year Plan (2016-2020) period, the construction of a railway line connecting Shigatse with Gyirong county, which has a checkpoint connecting Nepal and with Yatung county, a trade centre bordering India and Bhutan, will start.
Another railway line linking Lhasa to Nyingchi in the east is also expected to start soon.
Wang Chunhuan, professor at the Tibetan Academy of Social Sciences in Lhasa, told the Global Times Wednesday the network will play the role of continental bridge in south Asia and promote economic and cultural exchanges.
She also noted the development of Shigatse is crucial to boost the development of western Tibetan areas which have been lagging behind.
The rail line, apart from boosting economic development, will contribute to solve border disputes between China and India in the south Tibet region, says the paper, quoting observers.
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